Set against the backdrop of the 2012 London Olympics, Lethal White opens with a troubled young man named Billy Knight appearing in Cormoran Strike's office and describing a childhood memory: he witnessed a child being strangled in a field. He flees before giving Strike enough information to find him or verify the claim. When Strike is subsequently hired by Conservative government minister Jasper Chiswell to investigate an attempt at political blackmail — apparently unrelated to Billy's disturbing story — the two cases gradually converge.
The fourth Cormoran Strike novel is the longest in the series to that point, operating on multiple fronts simultaneously: the political plot threads through Westminster, the personal lives of Strike and Robin each reach a significant turning point, and the buried childhood trauma at the story's core is investigated with a patience that rewards readers who have followed the series from the beginning.
Published on 18 September 2018 under Rowling's Robert Galbraith pseudonym, Lethal White runs to 656 pages in its UK first edition — a deliberate change of pace: a more expansive, politically textured instalment that deepens the series' portrait of British institutions while maintaining the procedural rigour of its predecessors.